A structured document, such as a web page, may include page content such as text and images, layout information, and scripting codes. A layout engine is a software component containing code for rendering structured documents in a graphical user interface. A graphics processor or graphics processing unit (GPU) is a specialized circuit for efficiently manipulating geometrical representation of computer graphics and generating images for output to a display of a computing device. A GPU may include one or more integrated circuits or processing cores for carrying out mathematical operations commonly used in graphics rendering. A GPU may use a special graphics-unit instruction set or a central processing unit (CPU) or CPU-like (e.g. a modified x86) instruction set. A GPU may implement a number of graphics primitive operations, such as blitting, texture mapping, pixel shading, and frame buffering. In additional to three-dimensional (3D) hardware, a GPU may include basic two-dimensional (2D) acceleration and frame buffer capabilities. In addition, a GPU may support YUV color space and hardware overlays, as well as Motion Picture Experts Group (MPEG) primitives (such as motion compensation and inverse discrete cosine transform (iDCT)). A GPU may be a graphics accelerator, a general-purpose GPU (GPGPU), or any other suitable processor or processing unit. A GPU may be an individual chip in a computing device or part of a chip or multi-chip module containing a main processor of a computing device. A software application may access a GPU with an application programming interface (API) to the GPU. Examples of GPU APIs are OPENGL (managed by KHRONOS GROUP) and DIRECT3D by MICROSOFT.